1. Technical Field
The present invention relates generally to a display device, and particularly to a display device having a voltage commonly applied to each pixel through wiring.
2. Description of the Related Art
Currently, flat panel displays are widely used as display devices for various applications. Flat panel displays are generally classified into liquid crystal display, organic light emitting device, electrophoretic display, plasma display device, and micro-shutter display device.
Among them, liquid crystal display panel, which is one of the more common types of flat panel displays currently in use, comprises two sheets of substrates with field generating electrodes such as a pixel electrode and a common electrode, and a liquid crystal layer interposed therebetween. The liquid crystal display generates electric fields in the liquid crystal layer by applying voltages to the field generating electrodes, thereby determining the alignment of liquid crystal molecules in the liquid crystal layer and controlling polarization of incident light.
A storage capacitor receives a storage voltage to maintain liquid crystal molecules aligned by the electric field for a predetermined time period (one frame).
Also, according to a pixel structure of the liquid crystal display, one pixel is divided into at least two subpixels, and an element such as a transistor connected to the storage voltage may be used to apply different electric fields between the liquid crystal layers of the subpixels.
As described above, when a constant voltage such as the storage voltage is applied to each pixel through a wiring, the magnitude of the storage voltage varies according to the position of the pixel.
Also, in the liquid crystal display, in addition to the wiring (storage voltage line) transmitting the storage voltage, a gate line and a data line intersect each other such that the storage voltage line may intersect one of the wirings or partially overlap one of the wirings. In this case, a gate voltage signal or a data voltage signal applied to each pixel may be delayed.
The data voltage is changed every horizontal period 1H. However, the data voltage may be delayed by wiring, an electrode formed near the wiring, or an electrode formed on an opposing substrate.
Further, the aperture ratio or transmittance may be reduced by addition of separate wiring.
In addition, when forming a color filter in a lower panel, the cell gap is decreased at a position where the gate line and the data line cross such that a layer formed at the position where the gate line and the data line cross may be easily shorted to a common electrode of an upper panel.
This may be generated in other flat panel displays as well as the liquid crystal display, even if a storage voltage is not used, and the same problem may be generated in the case of a voltage (for example, a common voltage, a reference voltage, etc.) that is equally applied to a plurality of pixels through the wiring.
Meanwhile, among the liquid crystal displays, a vertically aligned mode liquid crystal display in which a long axis of the liquid crystal molecules are arranged to be perpendicular to a display panel in the state in which an electric field is not applied has been in the limelight due to a high contrast ratio and a wide reference viewing angle thereof. However, the vertically aligned mode liquid crystal display may not provide the same display quality when viewed from a side as when viewed from the front. In order to solve the problem, one pixel is partitioned into two subpixels and voltages of the two subpixels are adjusted to be different from each other to change transmittance. In this liquid crystal display, when differently controlling the voltages of the two subpixels, the voltage that is commonly applied inside the liquid crystal display may be changed.
The above information disclosed in this Background section is only for enhancement of understanding of the background of the invention and therefore it may contain information that does not form the prior art that is already known in this country to a person of ordinary skill in the art.